freebsd-dev/sys/dev/cpuctl/cpuctl.c
Nathan Whitehorn 96c85efb4b Replace a number of conflations of mp_ncpus and mp_maxid with either
mp_maxid or CPU_FOREACH() as appropriate. This fixes a number of places in
the kernel that assumed CPU IDs are dense in [0, mp_ncpus) and would try,
for example, to run tasks on CPUs that did not exist or to allocate too
few buffers on systems with sparse CPU IDs in which there are holes in the
range and mp_maxid > mp_ncpus. Such circumstances generally occur on
systems with SMT, but on which SMT is disabled. This patch restores system
operation at least on POWER8 systems configured in this way.

There are a number of other places in the kernel with potential problems
in these situations, but where sparse CPU IDs are not currently known
to occur, mostly in the ARM machine-dependent code. These will be fixed
in a follow-up commit after the stable/11 branch.

PR:		kern/210106
Reviewed by:	jhb
Approved by:	re (glebius)
2016-07-06 14:09:49 +00:00

558 lines
14 KiB
C

/*-
* Copyright (c) 2006-2008 Stanislav Sedov <stas@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/ioccom.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/sched.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/pcpu.h>
#include <sys/smp.h>
#include <sys/pmckern.h>
#include <sys/cpuctl.h>
#include <machine/cpufunc.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
static d_open_t cpuctl_open;
static d_ioctl_t cpuctl_ioctl;
#define CPUCTL_VERSION 1
#ifdef DEBUG
# define DPRINTF(format,...) printf(format, __VA_ARGS__);
#else
# define DPRINTF(...)
#endif
#define UCODE_SIZE_MAX (32 * 1024)
static int cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd,
struct thread *td);
static int cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data,
struct thread *td);
static int cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data,
struct thread *td);
static int cpuctl_do_update(int cpu, cpuctl_update_args_t *data,
struct thread *td);
static int update_intel(int cpu, cpuctl_update_args_t *args,
struct thread *td);
static int update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td);
static int update_via(int cpu, cpuctl_update_args_t *args,
struct thread *td);
static struct cdev **cpuctl_devs;
static MALLOC_DEFINE(M_CPUCTL, "cpuctl", "CPUCTL buffer");
static struct cdevsw cpuctl_cdevsw = {
.d_version = D_VERSION,
.d_open = cpuctl_open,
.d_ioctl = cpuctl_ioctl,
.d_name = "cpuctl",
};
/*
* This function checks if specified cpu enabled or not.
*/
static int
cpu_enabled(int cpu)
{
return (pmc_cpu_is_disabled(cpu) == 0);
}
/*
* Check if the current thread is bound to a specific cpu.
*/
static int
cpu_sched_is_bound(struct thread *td)
{
int ret;
thread_lock(td);
ret = sched_is_bound(td);
thread_unlock(td);
return (ret);
}
/*
* Switch to target cpu to run.
*/
static void
set_cpu(int cpu, struct thread *td)
{
KASSERT(cpu >= 0 && cpu <= mp_maxid && cpu_enabled(cpu),
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
thread_lock(td);
sched_bind(td, cpu);
thread_unlock(td);
KASSERT(td->td_oncpu == cpu,
("[cpuctl,%d]: cannot bind to target cpu %d on cpu %d", __LINE__, cpu, td->td_oncpu));
}
static void
restore_cpu(int oldcpu, int is_bound, struct thread *td)
{
KASSERT(oldcpu >= 0 && oldcpu <= mp_maxid && cpu_enabled(oldcpu),
("[cpuctl,%d]: bad cpu number %d", __LINE__, oldcpu));
thread_lock(td);
if (is_bound == 0)
sched_unbind(td);
else
sched_bind(td, oldcpu);
thread_unlock(td);
}
int
cpuctl_ioctl(struct cdev *dev, u_long cmd, caddr_t data,
int flags, struct thread *td)
{
int ret;
int cpu = dev2unit(dev);
if (cpu > mp_maxid || !cpu_enabled(cpu)) {
DPRINTF("[cpuctl,%d]: bad cpu number %d\n", __LINE__, cpu);
return (ENXIO);
}
/* Require write flag for "write" requests. */
if ((cmd == CPUCTL_WRMSR || cmd == CPUCTL_UPDATE) &&
((flags & FWRITE) == 0))
return (EPERM);
switch (cmd) {
case CPUCTL_RDMSR:
ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td);
break;
case CPUCTL_MSRSBIT:
case CPUCTL_MSRCBIT:
case CPUCTL_WRMSR:
ret = priv_check(td, PRIV_CPUCTL_WRMSR);
if (ret != 0)
goto fail;
ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td);
break;
case CPUCTL_CPUID:
ret = cpuctl_do_cpuid(cpu, (cpuctl_cpuid_args_t *)data, td);
break;
case CPUCTL_UPDATE:
ret = priv_check(td, PRIV_CPUCTL_UPDATE);
if (ret != 0)
goto fail;
ret = cpuctl_do_update(cpu, (cpuctl_update_args_t *)data, td);
break;
case CPUCTL_CPUID_COUNT:
ret = cpuctl_do_cpuid_count(cpu,
(cpuctl_cpuid_count_args_t *)data, td);
break;
default:
ret = EINVAL;
break;
}
fail:
return (ret);
}
/*
* Actually perform cpuid operation.
*/
static int
cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data,
struct thread *td)
{
int is_bound = 0;
int oldcpu;
KASSERT(cpu >= 0 && cpu <= mp_maxid,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
/* Explicitly clear cpuid data to avoid returning stale info. */
bzero(data->data, sizeof(data->data));
DPRINTF("[cpuctl,%d]: retrieving cpuid lev %#0x type %#0x for %d cpu\n",
__LINE__, data->level, data->level_type, cpu);
#ifdef __i386__
if (cpu_id == 0)
return (ENODEV);
#endif
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
cpuid_count(data->level, data->level_type, data->data);
restore_cpu(oldcpu, is_bound, td);
return (0);
}
static int
cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, struct thread *td)
{
cpuctl_cpuid_count_args_t cdata;
int error;
cdata.level = data->level;
/* Override the level type. */
cdata.level_type = 0;
error = cpuctl_do_cpuid_count(cpu, &cdata, td);
bcopy(cdata.data, data->data, sizeof(data->data)); /* Ignore error */
return (error);
}
/*
* Actually perform MSR operations.
*/
static int
cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, struct thread *td)
{
uint64_t reg;
int is_bound = 0;
int oldcpu;
int ret;
KASSERT(cpu >= 0 && cpu <= mp_maxid,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
/*
* Explicitly clear cpuid data to avoid returning stale
* info
*/
DPRINTF("[cpuctl,%d]: operating on MSR %#0x for %d cpu\n", __LINE__,
data->msr, cpu);
#ifdef __i386__
if ((cpu_feature & CPUID_MSR) == 0)
return (ENODEV);
#endif
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
if (cmd == CPUCTL_RDMSR) {
data->data = 0;
ret = rdmsr_safe(data->msr, &data->data);
} else if (cmd == CPUCTL_WRMSR) {
ret = wrmsr_safe(data->msr, data->data);
} else if (cmd == CPUCTL_MSRSBIT) {
critical_enter();
ret = rdmsr_safe(data->msr, &reg);
if (ret == 0)
ret = wrmsr_safe(data->msr, reg | data->data);
critical_exit();
} else if (cmd == CPUCTL_MSRCBIT) {
critical_enter();
ret = rdmsr_safe(data->msr, &reg);
if (ret == 0)
ret = wrmsr_safe(data->msr, reg & ~data->data);
critical_exit();
} else
panic("[cpuctl,%d]: unknown operation requested: %lu", __LINE__, cmd);
restore_cpu(oldcpu, is_bound, td);
return (ret);
}
/*
* Actually perform microcode update.
*/
static int
cpuctl_do_update(int cpu, cpuctl_update_args_t *data, struct thread *td)
{
cpuctl_cpuid_args_t args = {
.level = 0,
};
char vendor[13];
int ret;
KASSERT(cpu >= 0 && cpu <= mp_maxid,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
DPRINTF("[cpuctl,%d]: XXX %d", __LINE__, cpu);
ret = cpuctl_do_cpuid(cpu, &args, td);
if (ret != 0)
return (ret);
((uint32_t *)vendor)[0] = args.data[1];
((uint32_t *)vendor)[1] = args.data[3];
((uint32_t *)vendor)[2] = args.data[2];
vendor[12] = '\0';
if (strncmp(vendor, INTEL_VENDOR_ID, sizeof(INTEL_VENDOR_ID)) == 0)
ret = update_intel(cpu, data, td);
else if(strncmp(vendor, AMD_VENDOR_ID, sizeof(AMD_VENDOR_ID)) == 0)
ret = update_amd(cpu, data, td);
else if(strncmp(vendor, CENTAUR_VENDOR_ID, sizeof(CENTAUR_VENDOR_ID)) == 0)
ret = update_via(cpu, data, td);
else
ret = ENXIO;
return (ret);
}
static int
update_intel(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
void *ptr;
uint64_t rev0, rev1;
uint32_t tmp[4];
int is_bound;
int oldcpu;
int ret;
if (args->size == 0 || args->data == NULL) {
DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
return (EINVAL);
}
if (args->size > UCODE_SIZE_MAX) {
DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
return (EINVAL);
}
/*
* 16 byte alignment required. Rely on the fact that
* malloc(9) always returns the pointer aligned at least on
* the size of the allocation.
*/
ptr = malloc(args->size + 16, M_CPUCTL, M_WAITOK);
if (copyin(args->data, ptr, args->size) != 0) {
DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
__LINE__, args->data, ptr, args->size);
ret = EFAULT;
goto fail;
}
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
critical_enter();
rdmsr_safe(MSR_BIOS_SIGN, &rev0); /* Get current microcode revision. */
/*
* Perform update.
*/
wrmsr_safe(MSR_BIOS_UPDT_TRIG, (uintptr_t)(ptr));
wrmsr_safe(MSR_BIOS_SIGN, 0);
/*
* Serialize instruction flow.
*/
do_cpuid(0, tmp);
critical_exit();
rdmsr_safe(MSR_BIOS_SIGN, &rev1); /* Get new microcode revision. */
restore_cpu(oldcpu, is_bound, td);
if (rev1 > rev0)
ret = 0;
else
ret = EEXIST;
fail:
free(ptr, M_CPUCTL);
return (ret);
}
static int
update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
void *ptr = NULL;
uint32_t tmp[4];
int is_bound = 0;
int oldcpu;
int ret;
if (args->size == 0 || args->data == NULL) {
DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
return (EINVAL);
}
if (args->size > UCODE_SIZE_MAX) {
DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
return (EINVAL);
}
/*
* XXX Might not require contignous address space - needs check
*/
ptr = contigmalloc(args->size, M_CPUCTL, 0, 0, 0xffffffff, 16, 0);
if (ptr == NULL) {
DPRINTF("[cpuctl,%d]: cannot allocate %zd bytes of memory",
__LINE__, args->size);
return (ENOMEM);
}
if (copyin(args->data, ptr, args->size) != 0) {
DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
__LINE__, args->data, ptr, args->size);
ret = EFAULT;
goto fail;
}
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
critical_enter();
/*
* Perform update.
*/
wrmsr_safe(MSR_K8_UCODE_UPDATE, (uintptr_t)ptr);
/*
* Serialize instruction flow.
*/
do_cpuid(0, tmp);
critical_exit();
restore_cpu(oldcpu, is_bound, td);
ret = 0;
fail:
if (ptr != NULL)
contigfree(ptr, args->size, M_CPUCTL);
return (ret);
}
static int
update_via(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
void *ptr;
uint64_t rev0, rev1, res;
uint32_t tmp[4];
int is_bound;
int oldcpu;
int ret;
if (args->size == 0 || args->data == NULL) {
DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
return (EINVAL);
}
if (args->size > UCODE_SIZE_MAX) {
DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
return (EINVAL);
}
/*
* 4 byte alignment required.
*/
ptr = malloc(args->size, M_CPUCTL, M_WAITOK);
if (copyin(args->data, ptr, args->size) != 0) {
DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
__LINE__, args->data, ptr, args->size);
ret = EFAULT;
goto fail;
}
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
critical_enter();
rdmsr_safe(MSR_BIOS_SIGN, &rev0); /* Get current microcode revision. */
/*
* Perform update.
*/
wrmsr_safe(MSR_BIOS_UPDT_TRIG, (uintptr_t)(ptr));
do_cpuid(1, tmp);
/*
* Result are in low byte of MSR FCR5:
* 0x00: No update has been attempted since RESET.
* 0x01: The last attempted update was successful.
* 0x02: The last attempted update was unsuccessful due to a bad
* environment. No update was loaded and any preexisting
* patches are still active.
* 0x03: The last attempted update was not applicable to this processor.
* No update was loaded and any preexisting patches are still
* active.
* 0x04: The last attempted update was not successful due to an invalid
* update data block. No update was loaded and any preexisting
* patches are still active
*/
rdmsr_safe(0x1205, &res);
res &= 0xff;
critical_exit();
rdmsr_safe(MSR_BIOS_SIGN, &rev1); /* Get new microcode revision. */
restore_cpu(oldcpu, is_bound, td);
DPRINTF("[cpu,%d]: rev0=%x rev1=%x res=%x\n", __LINE__,
(unsigned)(rev0 >> 32), (unsigned)(rev1 >> 32), (unsigned)res);
if (res != 0x01)
ret = EINVAL;
else
ret = 0;
fail:
free(ptr, M_CPUCTL);
return (ret);
}
int
cpuctl_open(struct cdev *dev, int flags, int fmt __unused, struct thread *td)
{
int ret = 0;
int cpu;
cpu = dev2unit(dev);
if (cpu > mp_maxid || !cpu_enabled(cpu)) {
DPRINTF("[cpuctl,%d]: incorrect cpu number %d\n", __LINE__,
cpu);
return (ENXIO);
}
if (flags & FWRITE)
ret = securelevel_gt(td->td_ucred, 0);
return (ret);
}
static int
cpuctl_modevent(module_t mod __unused, int type, void *data __unused)
{
int cpu;
switch(type) {
case MOD_LOAD:
if (bootverbose)
printf("cpuctl: access to MSR registers/cpuid info.\n");
cpuctl_devs = malloc(sizeof(*cpuctl_devs) * (mp_maxid + 1), M_CPUCTL,
M_WAITOK | M_ZERO);
CPU_FOREACH(cpu)
if (cpu_enabled(cpu))
cpuctl_devs[cpu] = make_dev(&cpuctl_cdevsw, cpu,
UID_ROOT, GID_KMEM, 0640, "cpuctl%d", cpu);
break;
case MOD_UNLOAD:
CPU_FOREACH(cpu) {
if (cpuctl_devs[cpu] != NULL)
destroy_dev(cpuctl_devs[cpu]);
}
free(cpuctl_devs, M_CPUCTL);
break;
case MOD_SHUTDOWN:
break;
default:
return (EOPNOTSUPP);
}
return (0);
}
DEV_MODULE(cpuctl, cpuctl_modevent, NULL);
MODULE_VERSION(cpuctl, CPUCTL_VERSION);